Hans van der Maarel

Posted 23 November 2017 - 07:03 AM

Hans van der Maarel

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Netherlands

Do you have existing maps in raster format? You could try running those through a vectorizer and/or OCR service. Illustrator's vectorizer works okay-ish but I'd be weary to use it on something as complex as a nautical chart.

If you have vector data as input it would be a lot easier. At least the data quality would be good.

hphillips

Posted 07 December 2017 - 10:35 PM

hphillips

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11 posts

United States

If by vector nautical charts you mean S-57 Electronic Nautical Charts (ENC) to be used on shipboard Electronic Chart Display and Information Systems (ECDIS), then you are wading into really deep water :-). Topology has to be perfectly maintained through multiple layers when editing e.g. when polygon and a line have an edge in common. Additionally you have certain allowed objects and attributes, (some of which can be nested) and a required layer stack according to the IHO S-57 standard. As a result, to create and validate ENCs, chartmakers in that business use dedicated ENC production tools from Caris, SevenCs or ESRI ArcGIS with the Production Mapping and Maritime Charting extension.

There are several free tools and GIS extensions that will dissassemble an S-57 ENC into layers but only the few expensive tools I mentioned above that can put them together into the monolithic S57 ENC file containing the layered polygons, lines, points and objects that comprise the world as needed for navigation.

I am sure you are aware that you can download vector and raster nautical charts for the coastal US from NOAA. If you wanted to make your own simple (non S-57 ENC) nautical treasure map or fishing hole map, download one of the NOAA raster charts, convert BSB to GeoTIFF, load to a GIS, then add your fishing holes as a layer. Or with more work you could disassemble one of those vector NOAA charts, select out the layers you wanted in a GIS, then add your fishing holes as a layer.